Step adjustable monoaxial vibrator

A step adjustable vibrator comprising:

• a hollow housing defining a roller track surface on its interior;
• a balanced rotor mounted in said housing to rotate about an axis of rotation surrounded by said roller track surface, said rotor having a plurality of axially spaced roller receiving compartments extending transversely of said axis of rotation;
• a plurality of rollers carried by said rotor such that they roll along said roller track surface as said rotor turns, one roller being received in each of said compartments, at least a pair of first rollers being situated on one side of said axis of rotation, a second roller being carried by said rotor in a respective compartment extending to opposite sides of said axis of rotation whereby said second roller can be selectively situated on either side of said axis of rotation depending upon the selected step in adjustment of the mode of operation of the vibrator;
• and
• a movable blocking rod positioned along said axis of rotation and blocking moving of said second roller from one side of said axis of rotation to the other, said blocking rod being movable to unblock movement of said second roller and allows said second roller to move from one side of said axis to the other, whereby when said second roller is situated on the same side of said axis as said first roller, the vibrator generates vibration at a first level and when said second roller is situated on the opposite side of said axis from said first rollers, the vibrator generates vibrations at a second relatively lower level.